FACTORS INFLUENCING THE ONSET AND PROGRESSION OF DIABETIC-RETINOPATHYIN SUBJECTS WITH INSULIN-DEPENDENT DIABETES-MELLITUS

Background. The etiology of diabetic retinopathy is poorly understood. In the current study, factors associated with the onset and the progr ession or regression of retinopathy are evaluated. Methods: Two hundre d seventy-seven subjects with insulin-dependent (type I) diabetes mell itus (IDDM) were evaluated longitudinally for retinal changes over a m ean of 2.7 years. The multistate Markov model was used to analyze the influences of the duration of diabetes, a family history of hypertensi on, age, sex, cigarette smoking, systolic blood pressure, diastolic bl ood pressure, cholesterol levels, and longitudinal glycohemoglobin (GH b) values on the development and the progression or regression of reti nopathy. Results: Univariate analysis confirmed that four factors were significantly associated with the etiology and the progression or reg ression of diabetic retinopathy: age, duration of diabetes, mean longi tudinal GHb levels (all at P < 0.01), and diastolic blood pressure (P < 0.04). However, age was no longer significant when controlled by dur ation of diabetes. Cigarette smoking was only associated significantly with background retinopathy (stages 2 and 3). Systolic blood pressure , sex, a family history of hypertension, and cholesterol levels were n ot significantly associated with retinopathy. Conclusions: The onset o f diabetic retinopathy is associated with the duration of diabetes, me an longitudinal GHb levels, smoking, and diastolic blood pressure. A l onger duration of diabetes, higher GHb values, and higher diastolic bl ood pressure levels are associated with an increased risk of progressi on and a decreased chance of regression of diabetic retinopathy.